GIRK1 triggers multiple cancer-related pathways in the benign mammary epithelial cell line MCF10A

Gebhard Schratter,Astrid Gorischek,Susanne Scheruebel,Klaus Zorn-Pauly,Thomas Bauernhofer,Dieter Platzer,Helmut Ahammer,Stefanie Stanzer,Sonja Langthaler,Ruth Prassl,Kurt Schmidt,Stephan W Jahn,Trevor T J Devaney,Brigitte Pelzmann,Nassim Ghaffari-Tabrizi-Wizsy,Andreas Prokesch,Wolfgang Schreibmayer,Katja Ester,Simin Rezania

doi:10.1038/s41598-019-55683-w

Abstract

Excessive expression of subunit 1 of GIRK1 in ER+ breast tumors is associated with reduced survival times and increased lymph node metastasis in patients. To investigate possible tumor-initiating properties, benign MCF10A and malign MCF7 mammary epithelial cells were engineered to overexpress GIRK1 neoplasia associated vital parameters and resting potentials were measured and compared to controls. The presence of GIRK1 resulted in resting potentials negative to the controls. Upon GIRK1 overexpression, several cellular pathways were regulated towards pro-tumorigenic action as revealed by comparison of transcriptomes of MCF10AGIRK1 with the control (MCF10AeGFP). According to transcriptome analysis, cellular migration was promoted while wound healing and extracellular matrix interactions were impaired. Vital parameters in MCF7 cells were affected akin the benign MCF10A lines, but to a lesser extent. Thus, GIRK1 regulated cellular pathways in mammary epithelial cells are likely to contribute to the development and progression of breast cancer.

Highlights

G-Protein coupled receptors (GPCRs) represent one of the largest gene families in humans and comprise a sizeable number of plasma membrane bound sensors as cellular targets for endocrine signaling molecules
We could verify that the MCF10AGIRK1 and MCF7GIRK1 transfectant cell lines exhibit relevant overexpression of GIRK1 mRNA and protein compared to the respective WT lines
The present study demonstrates that overexpression of GIRK1 in benign mammary epithelial cell (MEC) triggers a profound transcriptional response, which includes numerous genes involved in several cellular pro-tumorigenic pathways

Summary

Introduction

G-Protein coupled receptors (GPCRs) represent one of the largest gene families in humans and comprise a sizeable number of plasma membrane bound sensors as cellular targets for endocrine signaling molecules. Opposed to this stands a handful of direct effectors for G-protein signaling. The malignant MCF7 breast cancer cell line expresses GIRK1 mRNA already at moderate levels, providing an excellent model for increased GIRK1 expression in breast tumours[17]. MEC lines based upon the malignant MCF7 line were engineered Their vital properties were assessed and the effects of GIRK1 overexpression was compared to the benign MEC line

Methods

Results

Conclusion